ED Mathématiques et Informatique
The long walk accross the quarter plane
by Pierre BONNET (LaBRI - Laboratoire Bordelais de Recherche en Informatique)
The defense will take place at 10h30 - Amphi LaBRI 351, cours de la Libération F-33405 Talence cedex
in front of the jury composed of
- Mireille BOUSQUET-MÉLOU - Directrice de recherche - LaBRI, Université de Bordeaux, CNRS - Directeur de these
- Alin BOSTAN - Directeur de recherche - Inria Saclay - Rapporteur
- Kilian RASCHEL - Directeur de recherche - LAREMA, Université d'Angers, CNRS - Rapporteur
- Charlotte HARDOUIN - Professeure des universités - IMT, Université Paul Sabatier - Directeur de these
- Vincent DELECROIX - Chargé de recherche - LaBRI, Université de Bordeaux, CNRS - Examinateur
- Julien ROQUES - Professeur des universités - ICJ, Université de Lyon 1 - Examinateur
- Frédérique BASSINO - Professeure des universités - LIPN, Université SorbonneParis Nord - Examinateur
We are interested in a topic in enumerative combinatorics, namely counting paths in a cone. Given a finite set of steps S, we want to count the paths whose steps are in S and which remain in the quarter plane at all times. This question naturally leads to the study of a functional equation verified by the generating series of such paths, called a catalytic variables equation. The study of this type of equation, via Galoisian theories, allows us to determine the nature of the solutions, which corresponds to a measure of the complexity of the paths based on this set of steps.
ED Sciences de la Vie et de la Santé
Neuroprotection of polyphenol supplementation via the modulation of the brain energetic metabolism.
by Pierre GOUDENECHE (Centre de Résonnance Magnétique des Systèmes Biologiques)
The defense will take place at 9h30 - Salle de conférence 146, rue Léo Saignat Bâtiment 4A – Zone Nord 33076 Bordeaux Cedex
in front of the jury composed of
- Monique BERNARD - Directrice de recherche - CNRS-Marseille - Examinateur
- Philippe EVRARD - Directeur d'études - Université de Paris Diderot - Examinateur
- Emmanuel BARBIER - Directeur de recherche - INSERM-Grenoble - Rapporteur
- Carine CLEREN - Maîtresse de conférences - INSERM-Rouen - Rapporteur
Neonatal hypoxia-ischemia (NHI) affects approximately 1.5‰ of newborns in developed countries and up to 20‰ in developing countries. It represents a major cause of mortality and long-term disability. This pathology results from a reduction in blood flow, leading to oxygen and energy substrate deficits in the brain. To date, moderate therapeutic hypothermia (TH) remains the only validated clinical intervention. However, nearly one in two infants does not respond favorably, and its implementation remains challenging in many contexts. In this regard, polyphenols, recognized for their neuroprotective properties, represent promising therapeutic candidates. The aim of this thesis was to evaluate the neuroprotective potential of maternal supplementation with passion fruit extract in a rat model of NHI, as well as its compatibility with TH. This work was structured around four main components: (i) Demonstration of the superior neuroprotective effect of a polyphenol cocktail compared to resveratrol alone: this study showed that a combination of polyphenols acting synergistically enhanced neuroprotection, more effectively reducing brain lesions and improving functional recovery than supplementation with resveratrol alone. (ii) Literature review to define the underlying mechanisms of polyphenol-induced neuroprotection in the context of NHI. (iii) Establishment of a hypothermia protocol: by comparing different post-HI treatment durations (2 h, 3 h, and 5 h), our results demonstrated that 2 h of TH was sufficient to significantly reduce brain lesions and improve behavioral outcomes, thereby defining a reference experimental protocol. (iv) Evaluation of the effects of maternal supplementation with passion fruit extract: this nutritional approach led to reduced lesion volumes and preservation of motor and cognitive functions, as confirmed by MRI, behavioral tests, and histological analyses. This supplementation also proved to be effectively compatible with hypothermia. In conclusion, these findings highlight the neuroprotective effect of maternal polyphenol supplementation in the context of neonatal HI. This simple and accessible nutritional strategy offers practical perspectives for improving HI management, particularly in developing countries where hypothermia remains difficult to implement.